Preheat your oven to 350°F (175°C) and grease and flour two 9-inch round cake pans.

In a medium-sized bowl, whisk together the all-purpose flour, baking powder, and salt until well combined.

In a large mixing bowl, cream the softened butter and granulated sugar together using an electric mixer on medium speed until the mixture is light and fluffy.

Add the eggs one at a time to the butter mixture, beating well after each addition.

Stir in the vanilla extract and mix until fully incorporated.

Gradually add the dry ingredients to the butter mixture, alternating with the milk, beginning and ending with the dry ingredients. Mix until just combined, being careful not to overmix.

Divide the batter evenly between the prepared cake pans and smooth the tops with a spatula.

Place the pans in the preheated oven and bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean.

Allow the cakes to cool in the pans for 10 minutes, then turn them out onto a wire rack to cool completely.

While the cakes are cooling, prepare the caramel sauce by combining the brown sugar, butter, and heavy cream in a medium saucepan over medium heat.

Stir the mixture continuously until the butter has melted and the sugar has dissolved completely.

Bring the mixture to a simmer, then reduce the heat to low and cook for 3-5 minutes, stirring occasionally, until the sauce thickens slightly.

Remove the caramel sauce from the heat and stir in the vanilla extract. Allow the caramel to cool slightly before using.

Once the cakes have cooled, place one layer on a serving plate and spread a generous amount of caramel sauce over the top.

Place the second cake layer on top of the first and drizzle more caramel sauce over the top and around the edges of the cake.

Allow the caramel to set for a few minutes before slicing and serving the cake.